Study of Ziegler-Natta /Metallocene Hybrid Catalyst on Pilot Device

In this work, Ziegler-Natta/Metallocene hybrid catalyst (Z-M) was prepared magnifying. The activity and copolymerization behavior of the catalyst were evaluated through 10L model device. Model experiment results confirmed that the catalyst was suitable for Spheripol-II PP pilot device. Subsequently, pilot experiment was carried out on 75 kgPP/h Spheripol-II PP pilot device. SP179 which was prepared by traditional Ziegler-Natta catalyst was used as a reference object. Pilot experiment results showed that: Z-M hybrid catalyst demonstrated good activity and copolymerization properties. The resultant polypropylene in-reactor alloys have better impact strength and flowability than SP179. These alloys showed good stiffness-toughness balance. The impact strength and the flexural modulus of the best alloy was 50 kJ/m2 at 23 °C and 848 MPa, respectively. The other performances were similar to that of SP179. But Z-M hybrid catalyst required lower feed ratio of ethylene than the traditional Ziegler-Natta catalyst for SP179.